A robot is referred to as an automatic doll which is made by assembling mechanical devices into a human-shaped doll to make its hand, feet and other parts act like humans. However, recently, an automatic apparatus autonomously performing any task has been collectively referred to as a robot regardless of a human figure.
Mobile robots have attracted considerable attention because they can perform a work instead of a person under extreme conditions or hazardous areas. Further, various kinds of mobile robots helping household works while autonomously moving around the house, such as cleaning robots, have widely spread.
In order for a mobile robot to perform a task while autonomously moving, recognition of surrounding environment is essential. The recognition of a robot to surrounding environment is conducted through a map. As a typical example of the map, there is a grid map in which surrounding space is expressed as grids having the same size and the presence or absence of an object is displayed in each of the grids. A robot creates a grid map for surrounding environment using a distance measuring sensor.
As the method of allowing a robot to create a grip map, there is a method in which a robot acquires distance information while rotating 360° in place and creates a grip map using the acquired distance information.
That is, a grid-based path planning method of setting a path for moving a mobile robot to goal point using the information confirmed from the grid map created as above is suitable for forming an optimized path of a mobile robot from starting point to goal point, but is problematic in that it takes much time to complete the setting of a path, and in that it is impossible to set a path planning for moving a mobile robot in real time under wide-area environment when considering the kinematic characteristics of the mobile robot.
Further, a sampling-based path planning method of finding a moving path to final goal point while expanding a tree by repeating the procedures of selecting the node nearest from the starting point of a mobile robot can set a path for moving the mobile robot in real time, but is problematic in that the ratio of an optimized path of moving the mobile robot to goal point is lowered, and in that there is a possibility of the path setting itself for moving the mobile robot to the goal point being failed due to inefficient sampling when considering the kinematic characteristics of the mobile robot.